France Rolls Out Rubis, Fifth Suffren-Class Attack Submarine, as One 1980s Boat Remains in Service

France's nuclear attack submarine Rubis, the fifth boat of the Suffren class, began its transfer on October 16 from Naval Group's construction hall at Cherbourg to the launch system in the Cachin basin, the DGA, France's defense procurement agency, said in a release the same day.

The Minister for the Armed Forces and Veterans presided over the ceremony, attended by the head of the DGA, according to the agency. "Rubis is a French success," the minister said. "It carries the work of the Cotentin, the excellence of our industry and the ambition of a whole nation."

Completion work will continue until the boat's first float-out, to be followed by alongside and sea trials conducted by state and industry teams and then delivery to the French Navy, the DGA said, without giving dates for any of these steps. Naval Group said the milestone came 17 months after the equivalent one for the fourth boat, De Grasse, according to Naval News, which expects alpha (first sea) trials by summer 2027 and delivery by the end of 2027, the outlet's own expectation rather than an official schedule.

Rubis belongs to the Barracuda program, run by the DGA to renew the SSN component of the French Navy. Of the four Suffren-class boats delivered so far, three have been admitted to active service, Suffren in 2022, Duguay-Trouin in 2024 and Tourville in 2025, and De Grasse, delivered in June 2026, will follow soon, the DGA said. Duguay-Trouin was commissioned on April 4, 2024, Tourville on July 4, 2025, and De Grasse was delivered on June 24, 2026.

The six boats ordered under Barracuda will replace the Rubis-class SSNs that entered service from the 1980s, the DGA said, so the new boat shares her name with the older class she is helping to replace. One boat of that older class, Améthyste (S605), remains in service after Émeraude was retired on December 12, 2024 and Perle on June 23, 2026.

GMN's French Navy inventory lists five SSNs: the four delivered Suffren-class boats, Suffren (S635), Duguay-Trouin (S636), Tourville (S637) and De Grasse (S638), plus Améthyste, with Rubis and Casabianca on order. Counting nuclear-powered attack submarines only, and excluding cruise-missile and ballistic-missile submarines, that places France fifth among the world's submarine fleets, behind the United States with 47, Russia with 12, China with 10 and the United Kingdom with 6. A comparison of the Suffren and British Astute classes sets the French design against its British counterpart.

The Suffren class brings new capabilities, according to the DGA: deploying special forces and striking land targets at depth with naval cruise missiles, while nuclear propulsion provides endurance and discretion. The agency said more than 10,000 people and 800 companies have been involved in the program, with 3,000 direct jobs, including 800 at subcontractors, mobilized each day.

The name honors the Free French minelaying submarine Rubis of the Second World War, which carried out 28 combat missions and laid 683 mines and was awarded the Croix de la Libération and the Croix de Guerre 1939-1945, the DGA said.

The sixth and last boat, Casabianca, is under construction, with delivery expected by 2030 in line with the 2024-2030 military programming law, according to the DGA.